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Chapter 11
CHAPTER 11
Backing Up Data
Computers fail—disks break, chips fry, wires short circuit, and drinks dribble into
the cases. Sometimes computers are stolen or are victims of human error. You may
lose not only hardware and software but, more importantly, data. Restoring lost data
takes time and money. In the meantime, your customers will be unhappy, and the
government may take an interest if the data is needed for compliance with regula-
tions. Making backup copies of all important data is cheap insurance against poten-
tially expensive disasters, and business continuity requires a backup and recovery
plan.
In this chapter we’ll cover several tools for backing up data that can be useful in dif-
ferent circumstances:
rsync
Sufficient for most user files; transfers files efficiently over a network to another
system, from which you can retrieve them if disaster strikes the local system
tar
Traditional Unix program for creating compressed collections of files; creates
convenient bundles of data that you can back up using other tools in this chapter
cdrecord/cdrtools
Records files to CD-Rs or DVDs
Amanda
Automates backups to tape; useful in environments with large amounts of data
MySQL tools
Provide ways to solve the particular requirements of databases